Internal-combustion engine with compressor



D 1954 M. MALLORY INTERNAL-COMBUSTION ENGINE WITH COMPRESSOR OriginalFiled May 21, 1948 B/NE EX FOR COOL! M W n 0 M United States Patent fINTERNAL-COMBUSTION ENGINE WITH COMPRESSOR assignor to The Mallory Micha corporation of No. 28,444, 1953, Serial 7 Claims. (Cl. 230-48) Thisinvention relates to a combined internal cornbustion engine and fluidcompressor, and has for its primary object to improve the constructionand operation of units of this character to enhance the practicabilityand commercial value thereof.

Another object is to provide such an arrangement, construction andoperation of the movable parts of the unit as to reduce to a minimum thethrust action of the ignited charges on the crankshaft, and to utilizethe crankshaft mainly as a timing means for the pistons, the ignitionand the valve mechanism.

Other objects of the invention will be apparent from the followingdescription, and from the accompany ng drawing, illustrating one emodiment thereof, in WhlCh Fig. l is a central vertical longitudinalsection of an apparatus embodying the invention, with parts in full andwith the engine piston approximately in firing position;

Fig. 2 is a fragmentary section with the engine piston at the end of itsfiring stroke and the compressor p1ston at the end of its compressingstroke, and

Fig. 3 is an enlarged detail, partly in section, of the floatingconnection of the piston connecting rods with each other and with thecrankshaft.

Referring to the drawing, 1 designates a cylinder unit having at one endan engine cylinder 2 and at 1ts other end a compressor cylinder 3, witha crank case 4 therebetween. A crankshaft 5 is journaled in the sides ofthe crank case 4 and has a wrist-pin 6 in the case. A power piston 7 ismounted in the cyl1nder 2 and cooperates with its outer end to form acombustlon chamberS. A compressor piston 9 is mounted in the cylinder 3and cooperates with its outer end to form a compressor chamber 10. Thepistons 7 and 9 are connected at their inner ends to the wrist-pin 6 byrespective connecting rods 11 and 12, the connection being such thatwhen the engine piston is at the limit of its out or compression stroke,the compressor piston 9 is at the lnn t of its in or suction stroke, asshown in Fig. 2.

Each connecting rod 11, 12, has a loose or floatlng connection with thewrist-pin 6, and the rods are connected without play to each other. Thisis accompl shed by rotatably mounting the inner ends of the twoconnecting rods without clearance, other than to provide a free turningfit, on a bearing sleeve 13, which in turn is mounted with a clearance14 for limited floating movements on the wrist-pin 6. This permits oneor the other of the sleeve and piston to have lagging movements relativeto the other during running of the apparatus for the purpose hereinafterdescribed.

The engine operates on the two-cycle principle and its cylinder 2 hasthe intake port 15 and the exhaust port 16 located to be uncovered tothe combustion chamber by the piston at the inner end of its stroke, theexhaust port being uncovered preferably slightly in advance of theintake port, as is customary. The cylinder 2 is provided at the outerend of the combustion chamber with a sparkplug 17 for igniting thecharges. Carbureted fuel charges are introduced into the cylinderthrough the port 15 from a line 18 which is opened to an air supplysource, and has a fuel jet 19 discharging in a restricted portionthereof toward the port 15. A throttle 20 is disposed between the fueljet and the port.

The outer or compression end of the compressor cylinder has a rotaryvalve 21 mounted therein and pro- 2,696,343 Patented Dec. 7, 1954 videddiametrically therethrough with a port 22, which during rotation opensconnection first between the compressor cylinder 10 and an air inletport 23 and then between the compressor cylinder and an outlet port 24.The valve 21 is connected to the crankshaft 5 to operate in synchronismtherewith, in the present instance at a one to two ratio, so that thecrank makes two revolutions to one of the valve. The arrangement is suchthat the valve port 22 opens communication between the intake port 23and the cylinder 10 during approximately the full in or suction strokeof the compressor piston, and then closes such port and openscommunication between the cylinder 10 and the outlet port 24 duringsubstantially the entire out or compression stroke of the piston.

In practice, it is preferable to close the valve port 22 to the intakeport 23 slightlybefore the piston completes its in or suction stroke andat approximately the same time, but after such closing, to open thecylinder to the outlet port, this latter opening taking place atapproximately the same time as the ignition of the power charge.

The inlet port 23 preferably opens to the atmosphere, and the outletport 24 preferably connects through a pipe 25 with an air charge storagetank 26. The tank 26, in the present instance, has connection with theair charge line 18 to serve as its supply source and is also shown ashaving connection through a line 27 with an air turbine 28, the rotor ofwhich is mounted on the crankshaft 5 so that air pressure from the tankis utilized to assist in the driving of the shaft. In addition to theair turbine 28, the usual flywheel (not shown) is preferably provided onthe crankshaft. The tank may also have a valve controlled outlet 29whereby the compressed storage air may be used for any desired purpose.

In the use of the present apparatus, the main power of the combustion inthe engine cylinder is not transferred through the crankshaft to deliverpower to the compressor unit, as is customarily the case with apparatusof this type, but most of the power generated by the combustion istransferred through the piston connections 11, 12 and 13 directly to thecompressor piston 9 instead of through the crankshaft. The crankshaftplays more the function of timing the piston, the ignition and the valvemechanism. Naturally, due to thefloating action of the sleeve 13 on thecrankshaft, there is little stress on the bearings of the shaft and onthe connecting rod bearings, and a small crankshaft and bearingstherefor and for the connecting rods can be used.

Assuming, in operation, that the compressor piston 9 has reached the endof its intake stroke, an atmospheric charge has been drawn through port23 and rotary valve port 22, but as the piston 9 reaches the end of itsintake stroke, port 22 ceases communication with port 23 and makescommunication with the outlet port 24. The pressure in tank 26 beinghigher than atmospheric pressure immediately flows back into theatmospheric pressure or the existing pressure drawn into the cylinderthrough port 23 on the intake stroke of the piston. The explosion thentakes place in the engine cylinder and the explosive force on the enginepiston 7 is directly against the maximum air pressure in the tank 26,which is now open to the compressor cylinder 10, especially after theengine crank has moved slightly past dead center. The explosive force iscommunicated directly through the pistons and connecting rods instead ofto the crankshaft and then to the compressor piston due to the sleevebearing 13 being mounted for limited play or clearance on the crankshaftwhile its bearing in the inner ends of the connecting rods 11 and 12 iswithout clearance. This explosive force is also against the airpressures or tank pressures in the compressor chamber 10 at thebeginning of the explosion, inasmuch as the rotary valve 21 will at thetime of explosion be in a position to connect the air pressure in thetank 26 with the compression cylinder 10. Therefore, the air pressure inthe tank will be directly against the combustion pressure in theengine-cylinder, thus relieving much of the load from the crankshaft.This eliminates to a great extent dead center of the engine unit. Inother words, if the crankshaft was not used and the connecting rods 11and 12 were solidly connected together, the entire explosive force wouldbe against the air pressure and there would beno dead center. Of course,however, with such a eonstructiomdifficulties would arise due to propertiming of the pistons, the igntion and the valve. The crankshaft is usedfor timing and, of course, to store energy ;to cause compression inengine cylinders and to complete scavenging of 'the aircornpressorcylinder during starting of the engine and to assist in the startingoperation.

With'the clearance provided between the connecting rod bearing sleeve 13and the crankshaft, once the crankshaft is started, the flywheel speedwill not be delivering the load-of the engine, but will be running morefreely and tend to travel ahead or lead the pistons. If the loadincreases, that is, the air pressure builds up in the tank 26 andcompression cylinder 10, to oppose combustion to the-extent that thepistons would tend to slow down, the flywheel speed, or the airturbinespeed, will take the lead. If an air turbine 28 is employed in additionto the'flywheel, the tank or other pressure for actuating the turbinewill always keep the flywheel pullingagainst the pistons, and of'courseif the air pressure is from the storage tank 26, there is no loss ofpower because the power used from the tank to keep the turbine turningis added back to the engine power.

It is important for proper operation that the area of the compressorcylinder be larger than that of the combustion cylinder. The reason forthis is that the combustion pressures are much higher than thecompression pressures. For instance, supposing the combustion pressuresto be 400 pounds per square inch and the cylinders had an area ratio oftwo to one with the compression cylinder the larger, the air compressionpiston having twice the areaof the combustion piston would causepractically a balance. If the cylinders were one to one, the volume ofair handled would be low. The idea is to use a large volume of air undera lower pressure than the combustion pressures. Naturally, thecombustion piston would be smaller than the compression piston, and theair pressure obtained depends-on the area ratio of the two pistons.

I wish it understood that my invention is not limited to any specificconstruction, arrangement or form of the parts, as it is capable ofnumerous modifications and changes without departing from the spirit ofthe claims.

This application is a continuation of my application Serial No; 28,444,filed May 21, 1948, now abandoned.

I claim:

1. Aninternal combustion engine and fluid compressor unit comprising incombination opposed engine and compressor cylinders, a piston in eachcylinder, a direct connectlon between said pistons for driving thecompressor piston from the engine piston and constructed and arranged sothat the engine piston is at the end of its compression stroke when thecompressor piston is at the end of its suction stroke and the enginepiston travels on its power stroke as the compressor piston travels onits compression stroke, said compressor cylinder having fluid inlet andoutlet ports, valve means cooperating with said ports for'selectivelyopening and closing said ports, a fluid reservoir in communication withsaid outlet port, and means loosely connected to and driven by saidengine piston and connected to said valve means for moving said valvemeans to open or closed position with respect to said ports in timedrelation with the reciprocating compressor piston whereby upon thesuction stroke of said compressor piston the inlet port is open and theoutlet port is closed and upon the compression stroke of said compressorpiston the inlet port is closed and the outlet port is open to place thecompressor cylinder and fluid reservoir in communication, said directconnection between said pistons and said means loosely connected to saidengine piston being adapted to admit substantially the full pressure ofthe fluid charge in the reservoir against the compressor piston wherebythe explosive force on the engine piston during the power stroke will beexerted directly against the fluid under pressure in said compressorcylinder and reservoir.

2. The internal combustion engine and fluid compressor unit claimed inclaim 1 wherein the inlet port of said compressor cylinder opensdirectly to atmosphere so that the compressor piston on its suctionstroke draws in a charge of atmospheric air.

3. The internal combustion engine and fluid compressor unitcomprisingthe-means loosely 'connected to said engine piston defined inclaim 2 including a crankshaft driven by said connection and timingmeans driven ofl said crankshaft and connected to said valve means foropening and closing the said valve means which controls the inlet andoutlet ports of said compressor cylinder, substantially allof theexplosiveforce on the engine piston being transferred directlythroughsaid connection to the compressor. piston and said crankshaft servingprimarily to time the opening and closingof said valve means.

4. The internal combustion engine and fluid compressor unit as definedin claim 3 wherein said valve means comprises a rotary valve which opensthe inlet port-as it closes the :outlet .port and closes the .inlet portas it opens the outlet port.

5. An internal combustion engine construction comprising, anengine-crankshaft, an engine cylinder with a power piston therein, aconnecting rod pivotally connected at oneend to thepower piston,anzair-compressing cylinder with .a compression piston therein, aconnecting rod pivotally connected at one end to the compressorpiston,means pivotally connecting the opposite-end of each connecting rod to athrow of the crankshaft, the compressing cylinder having an inlet: portto the atmosphere and having anoutle'tporbfor compressed air, areservoir for compressed air, conduit means connecting the reservoir tothe outlet port,rnotor means operable by compressed air and connectedtothe zreservoir {and arranged to apply torque to the crankshaft, thetwo pistons being so related that when the power piston is substantiallyat-the limit of its compression stroke'the compressor piston? issubstantially at the limit'of its intake stroke and the throw of thecrankshaft approximates a dead center position, valve means forcontrolling said inlet and .outlet ports, valve-operatingmeans connectedwith saidvalve means and operable by the crankshaft and timed by thecrankshaft to operate said valve means to open the exhaust portandestablish an open connection between the reservoir and the compressingcylinder when the two pistons are substantially in the stated positions,so that the substantially full, pressure of the compressed air inthereservoir is active upon the compressor piston substantially immediatelyat .the start of the power stroke of the power piston, whereby the peakpressure of the powerstroke is utilized for further compression oftheairzand the crankshaft is relieved of the peak pressure whensthethrow of'thecrankshaft approximates a dead center position.

6. The engine construction as recited in claim 5 characterized in thatthere is means which connects :the. said opposite ends of the connectingrods to each other with a snug pivotal connection. and" additionallyconnects said ends of'the connecting rods to the .throw of thecrankshaftwith a loose pivotal connection, whereby the throw of thecrankshaft may lead themovement of the power piston.

7. The engine construction as recited in claim 6 characterized in thatthe means which connects the said opposite ends of the connecting rodsis a sleeve to which the said ends of the connecting rods are pivotallyconnected, said sleeve-being mounted on a throw of the crankshaft andhaving an internal diameter in excess of the diameter-of the throw toprovide the loose connection.

References Cited in the file of this patent UNITED STATESPATENTS NumberName Date 328,522 Richards Oct. 20, 1885 753,787 Dean Mar. 1, 1904785,713 Clark Mar. 28, 1905 1,011,400 Bergstrom Dec. 12, 1911 1,062,308Thuinmel .May 20, 1913 1,086,180. Ibach Feb. 3, 1914 1,165,539Praetorius Dec. 28, 1915 1,276,891 Felix- Aug. 27, 1918 1,475,381 GehresNov.-27, 1923 1,881,789 Mantle Oct. 11, 1932 2,002,200 Gehres May 21,1935 2,394,904 Fowler Feb. 12, 1946

